How mounting makes content available without reading?
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user3539Nov 25 '12 at 16:00

I edited the answer: the files and folders are available but are not read until copied/opened/...
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MatteoNov 25 '12 at 16:15

1

When you mount it, all it does is read the index of files/folders from the ISO which tells the operating system the name and starting block of each file. So reading that is trivial, that's why it is fast and that's what is meant by "making content available".
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tpg2114Nov 25 '12 at 21:16